1. Technical Field
The present invention relates to a pressure contact terminal, and more specifically to a pressure contact terminal of two-part structure having a spring piece for providing a secure contact pressure for a mated terminal.
2. Description of the Related Art
FIGS. 1A and 1B show an example of prior art pressure contact terminals of two-part structure, which is disclosed in Japanese Published Unexamined Utility Model Application No. 3-127770. This prior art contact pressure terminal 1 of two-part structure is roughly composed of a main body 2 and a pressure contact member 3. This contact pressure terminal 1 is used being pressure-connected with an end conductor of an electric wire 4.
The main body 2 is formed with a box portion 21 and a spring piece 22 both formed integral with the main body 2. The box portion 21 accommodates a male terminal 5 mated with the female contact pressure terminal 1, and the spring piece 22 provides a secure contact pressure to the mated male terminal 5. On the rear side (the right side in FIG. 1A), a pair of side plates 23 are vertically provided, and further two wire supporting walls 23a are formed on each of the front and rear sides of the side plates 23 by bending the front and rear ends of the two wire supporting walls 23a inward, respectively. Further, between the two wire supporting walls 28a on both the front and rear sides, two vertical walls 24 are formed, as shown in FIG. 1B, so as to provide a gap 25 between the two wire supporting walls 23a and each vertical wall 24, respectively.
The pressure contact member 3 separated from the main body 2 is of U-shaped, which is formed with two opposing pressure contact plates 31 arranged with an interval in the wire extending direction. Each pressure contact plate 31 is formed with a pressure contact groove 32 extending beginning from the middle thereof in the vertical direction and with a pressure contact blade 33 inclined downward and outward at the lower end thereof. Therefore, when the pressure contact member 3 is pushed downward into the gaps 25 formed between the wire supporting walls 23a and the vertical walls 24 from above, since the pressure contact blade 33 cuts off the wire cover of a wire 4 mounted on the two wire supporting walls 23a, the internal conductor of the wire 4 is inserted into the pressure contact grooves 32, so that the conductor of the wire 4 can be connected to the pressure contact plate 31 electrically.
Further, under these conditions, when the male terminal 5 is inserted into the box portion 21 of the pressure contact terminal 1 from the front side, it is possible to connect the male terminal 5 with the wire 4 through three different contact portions of between the spring piece 22 in the box portion 21 and the male terminal 5, between the main body 2 and the pressure contact member 3, and between the pressure contact plates 31 and the wire 4.
In the above-mentioned prior art contact pressure terminal 1, however, after the male terminal 5 has been mated with the female pressure contact terminal 1, when the conduction conditions are not kept excellent at the three contact portions, respectively, the conduction reliability of the pressure contact terminal deteriorates as the whole. In other words, in the prior art contact pressure terminal, since the wire 4 is connected to the male terminal 5 via three different contact portions, there exists a problem in that there exists such a possibility that the conduction reliability of the terminal deteriorates easily.